The term television receiver as used herein includes television receivers having a display device (commonly known as television sets) and television receivers without a display device, such as videocassette recorders (VCR's). Many modern television receivers include circuitry for generating an on-screen indication useful for tuning the television receiver to selected channels.
In medium-priced and higher-priced television receivers, the inclusion of an alphanumeric on-screen display (OSD) generator circuit for providing an on-screen display of programming information such as channel number is quite common. However, in lower-priced television receivers, the use of a separate OSD circuit is generally not cost-effective.
It is known in lower-cost television receivers to use a vertical tuning bar to display tuning information. In such a system the relative horizontal portion of the vertical tuning bar is indicative of channel number. The horizontal displacement of the tuning bar is generally a function of magnitude of the tuning voltage required to tune each channel. Band information (VHF-low, VHF-high, UHF in the United States or Bands I, II, III and UHF in Europe) is usually indicated by the color of the tuning bar. Such a system as described thus far is known from U.S. Pat. No. 4,410,913 (Chin et al.) issued Oct. 18, 1983.
The lowest-priced television receivers of all tend to be monochrome portable television receivers. Such receivers need an inexpensive and non-complex arrangement for producing a display of programming positions. Such receivers would also benefit from the use of the low-cost tuning bar display of Chin et al. but clearly cannot use the color of the tuning bar as a tuning band indication.